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        <h1>
          <div class="m-doc-template">template&lt;typename Input, typename Output, typename C&gt;</div>
          <span class="m-breadcrumb"><a href="namespacetf.html">tf</a>::<wbr/></span>DataPipe <span class="m-thin">class</span>
        </h1>
        <p>class to create a stage in a data-parallel pipeline</p>
        <nav class="m-block m-default">
          <h3>Contents</h3>
          <ul>
            <li>
              Reference
              <ul>
                <li><a href="#pub-types">Public types</a></li>
                <li><a href="#typeless-methods">Constructors, destructors, conversion operators</a></li>
                <li><a href="#pub-methods">Public functions</a></li>
              </ul>
            </li>
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<p>A data pipe represents a stage of a data-parallel pipeline. A data pipe can be either <em>parallel</em> direction or <em>serial</em> direction (specified by <a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">tf::<wbr />PipeType</a>) and is associated with a callable to invoke by the pipeline scheduler.</p><p>You need to use the template function, <a href="namespacetf.html#a8975fa5762088789adb0b60f38208309" class="m-doc">tf::<wbr />make_data_pipe</a>, to create a data pipe. The input and output types of a <a href="classtf_1_1DataPipe.html" class="m-doc">tf::<wbr />DataPipe</a> should be decayed types (though the library will always decay them for you using <code><a href="http://en.cppreference.com/w/cpp/types/decay.html" class="m-doc-external">std::<wbr />decay</a></code>) to allow internal storage to work. The data will be passed by reference to your callable, at which you can take it by copy or reference.</p><pre class="m-code"><span class="n">tf</span><span class="o">::</span><span class="n">make_data_pipe</span><span class="o">&lt;</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">string</span><span class="o">&gt;</span><span class="p">(</span>
<span class="w">  </span><span class="n">tf</span><span class="o">::</span><span class="n">PipeType</span><span class="o">::</span><span class="n">SERIAL</span><span class="p">,</span><span class="w"> </span>
<span class="w">  </span><span class="p">[](</span><span class="kt">int</span><span class="o">&amp;</span><span class="w"> </span><span class="n">input</span><span class="p">)</span><span class="w"> </span><span class="p">{</span><span class="k">return</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">to_string</span><span class="p">(</span><span class="n">input</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">100</span><span class="p">);}</span>
<span class="p">);</span></pre><p>In addition to the data, you callable can take an additional reference of <a href="classtf_1_1Pipeflow.html" class="m-doc">tf::<wbr />Pipeflow</a> in the second argument to probe the runtime information for a stage task, such as its line number and token number:</p><pre class="m-code"><span class="n">tf</span><span class="o">::</span><span class="n">make_data_pipe</span><span class="o">&lt;</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">string</span><span class="o">&gt;</span><span class="p">(</span>
<span class="w">  </span><span class="n">tf</span><span class="o">::</span><span class="n">PipeType</span><span class="o">::</span><span class="n">SERIAL</span><span class="p">,</span><span class="w"> </span>
<span class="w">  </span><span class="p">[](</span><span class="kt">int</span><span class="o">&amp;</span><span class="w"> </span><span class="n">input</span><span class="p">,</span><span class="w"> </span><span class="n">tf</span><span class="o">::</span><span class="n">Pipeflow</span><span class="o">&amp;</span><span class="w"> </span><span class="n">pf</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w">    </span><span class="n">printf</span><span class="p">(</span><span class="s">&quot;token=%lu, line=%lu</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span><span class="w"> </span><span class="n">pf</span><span class="p">.</span><span class="n">token</span><span class="p">(),</span><span class="w"> </span><span class="n">pf</span><span class="p">.</span><span class="n">line</span><span class="p">());</span>
<span class="w">    </span><span class="k">return</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">to_string</span><span class="p">(</span><span class="n">input</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">100</span><span class="p">);</span>
<span class="w">  </span><span class="p">}</span>
<span class="p">);</span></pre>
        <section id="pub-types">
          <h2><a href="#pub-types">Public types</a></h2>
          <dl class="m-doc">
            <dt id="a5cc3b76f16379f4cb2ecdef66dee1ba3">
              using <a href="#a5cc3b76f16379f4cb2ecdef66dee1ba3" class="m-doc-self">callable_t</a> = C
            </dt>
            <dd>callable type of the data pipe</dd>
            <dt id="ae5e9dd100a02edb2d560e8a1d516037d">
              using <a href="#ae5e9dd100a02edb2d560e8a1d516037d" class="m-doc-self">input_t</a> = Input
            </dt>
            <dd>input type of the data pipe</dd>
            <dt id="a8a99a980f0fa6bc55203cb33f526f007">
              using <a href="#a8a99a980f0fa6bc55203cb33f526f007" class="m-doc-self">output_t</a> = Output
            </dt>
            <dd>output type of the data pipe</dd>
          </dl>
        </section>
        <section id="typeless-methods">
          <h2><a href="#typeless-methods">Constructors, destructors, conversion operators</a></h2>
          <dl class="m-doc">
            <dt id="a8b7e8194874901eacfb5d3d2b72a2b85">
              <span class="m-doc-wrap-bumper"><a href="#a8b7e8194874901eacfb5d3d2b72a2b85" class="m-doc-self">DataPipe</a>(</span><span class="m-doc-wrap">) <span class="m-label m-flat m-info">defaulted</span></span>
            </dt>
            <dd>default constructor</dd>
            <dt>
              <span class="m-doc-wrap-bumper"><a href="#a542531895cb9363c6291e0ce9d126974" class="m-doc">DataPipe</a>(</span><span class="m-doc-wrap"><a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">PipeType</a> d,
              <a href="classtf_1_1DataPipe.html#a5cc3b76f16379f4cb2ecdef66dee1ba3" class="m-doc">callable_<wbr />t</a>&amp;&amp; callable)</span>
            </dt>
            <dd>constructs a data pipe</dd>
          </dl>
        </section>
        <section id="pub-methods">
          <h2><a href="#pub-methods">Public functions</a></h2>
          <dl class="m-doc">
            <dt>
              <span class="m-doc-wrap-bumper">auto <a href="#a82ef8e8f06444b251ccfe323facbf67a" class="m-doc">type</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">PipeType</a></span>
            </dt>
            <dd>queries the type of the data pipe</dd>
            <dt id="af7a3c2d313edd443b049e937f8ec8cd8">
              <span class="m-doc-wrap-bumper">void <a href="#af7a3c2d313edd443b049e937f8ec8cd8" class="m-doc-self">type</a>(</span><span class="m-doc-wrap"><a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">PipeType</a> type)</span>
            </dt>
            <dd>assigns a new type to the data pipe</dd>
            <dt>
              <div class="m-doc-template">template&lt;typename U&gt;</div>
              <span class="m-doc-wrap-bumper">void <a href="#a5931f0ae2db8e00f4ad4c42a26adbeae" class="m-doc">callable</a>(</span><span class="m-doc-wrap">U&amp;&amp; callable)</span>
            </dt>
            <dd>assigns a new callable to the data pipe</dd>
          </dl>
        </section>
        <section>
          <h2>Function documentation</h2>
          <section class="m-doc-details" id="a542531895cb9363c6291e0ce9d126974"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename Input, typename Output, typename C&gt;
              </div>
              <span class="m-doc-wrap-bumper"> tf::<wbr />DataPipe&lt;Input, Output, C&gt;::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#a542531895cb9363c6291e0ce9d126974" class="m-doc-self">DataPipe</a>(</span><span class="m-doc-wrap"><a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">PipeType</a> d,
              <a href="classtf_1_1DataPipe.html#a5cc3b76f16379f4cb2ecdef66dee1ba3" class="m-doc">callable_<wbr />t</a>&amp;&amp; callable)</span></span>
            </h3>
            <p>constructs a data pipe</p>
<p>You should use the helper function, <a href="namespacetf.html#a8975fa5762088789adb0b60f38208309" class="m-doc">tf::<wbr />make_data_pipe</a>, to create a <a href="classtf_1_1DataPipe.html" class="m-doc">DataPipe</a> object, especially when you need <a href="classtf_1_1DataPipe.html" class="m-doc">tf::<wbr />DataPipe</a> to automatically deduct the lambda type.</p>
          </div></section>
          <section class="m-doc-details" id="a82ef8e8f06444b251ccfe323facbf67a"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename Input, typename Output, typename C&gt;
              </div>
              <span class="m-doc-wrap-bumper"><a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564" class="m-doc">PipeType</a> tf::<wbr />DataPipe&lt;Input, Output, C&gt;::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#a82ef8e8f06444b251ccfe323facbf67a" class="m-doc-self">type</a>(</span><span class="m-doc-wrap">) const</span></span>
            </h3>
            <p>queries the type of the data pipe</p>
<p>A data pipe can be either parallel (<a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564adf13a99b035d6f0bce4f44ab18eec8eb" class="m-doc">tf::<wbr />PipeType::<wbr />PARALLEL</a>) or serial (<a href="namespacetf.html#abb7a11e41fd457f69e7ff45d4c769564a7b804a28d6154ab8007287532037f1d0" class="m-doc">tf::<wbr />PipeType::<wbr />SERIAL</a>).</p>
          </div></section>
          <section class="m-doc-details" id="a5931f0ae2db8e00f4ad4c42a26adbeae"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename Input, typename Output, typename C&gt;
                template&lt;typename U&gt;
              </div>
              <span class="m-doc-wrap-bumper">void tf::<wbr />DataPipe&lt;Input, Output, C&gt;::<wbr /></span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#a5931f0ae2db8e00f4ad4c42a26adbeae" class="m-doc-self">callable</a>(</span><span class="m-doc-wrap">U&amp;&amp; callable)</span></span>
            </h3>
            <p>assigns a new callable to the data pipe</p>
            <table class="m-table m-fullwidth m-flat">
              <thead>
                <tr><th colspan="2">Template parameters</th></tr>
              </thead>
              <tbody>
                <tr>
                  <td style="width: 1%">U</td>
                  <td>callable type</td>
                </tr>
              </tbody>
              <thead>
                <tr><th colspan="2">Parameters</th></tr>
              </thead>
              <tbody>
                <tr>
                  <td>callable</td>
                  <td>a callable object constructible from the callable type of this data pipe</td>
                </tr>
              </tbody>
            </table>
<p>Assigns a new callable to the pipe using universal forwarding.</p>
          </div></section>
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